All categories

4 years ago

Please please help me

Mathematics

1 answer:

qwelly [4]4 years ago

4 0

Answer:

BF = 30

Step-by-step explanation:

Each midsegment is half the length of the parallel side of the triangle. CE is 60 and is parallel to BF, so BF = 60/2 = 30.

You might be interested in

(2+4i)+(9+6i) find the sum of the complex numbers

eimsori [14]

^_^ #_#

Step-by-step explanation:

12492218293^-<

5 0

3 years ago

Read 2 more answers

the two-way table shows the attendant careers among the incoming class of first-year college students, divided by gender. If a f

vazorg [7]

Answer: 4.64%

$\dfrac{\text{female research scientist}}{\text{female total}}=\dfrac{103}{2219}=0.0464\quad =\large\boxed{4.64\%}$

6 0

3 years ago

Let vector u = (a, b) and vector v = (c, d). If the vectors are located as shown in the graph, then

AlekseyPX

We have the following vectors:
u = (a, b)
v = (c, d)
We observe that the vectors form an angle of 90 degrees.
Therefore, the product u.v is equal to zero.
We have then:
u.v = (a, b). (c, d) = 0
u.v = ac + bd = 0
ac = -bd
Answer:
B) ac = -bd

6 0

3 years ago

Help!! the second file are the answers

Inessa [10]

Answer:

<1 <2 and <1 <4

Step-by-step explanation:

A supplementary angle is a straight line with 180 degrees.

5 0

4 years ago

Read 2 more answers

If E(X)=100, E(Y)=120, E(Z) = 130, Var(X) = 9, Var(Y) = 16, Var(Z) = 25, Cov(X, Y)= - 10 Cov(X,Z) = 12, and Cov(Y,Z) = 14, then

vredina [299]

Answer:

(1) -0.833

(2) 0.80

(3) 0.70

(4) 390

(5) 90

(7) 48

Step-by-step explanation:

Given:

E (X) = 100, E (Y) = 120, E (Z) = 130

Var (X) = 9, Var (Y) = 16, Var (Z) = 25

Cov (X, Y) = -10, Cov (X, Z) = 12, Cov (Y, Z) = 14

The formulas used for correlation is:

$Corr (A, B) = \frac{Cov (A, B)}{\sqrt{Var (A)\times Var(B)}} \\$

(1)

Compute the value of Corr (X, Y)-

$Corr (X, Y) = \frac{Cov (X, Y)}{\sqrt{Var (X)\times Var(Y)}} \\=\frac{-10}{\sqrt{9\times16}} \\=-0.833$

(2)

Compute the value of Corr (X, Z)-

$Corr (X, Z) = \frac{Cov (X, Z)}{\sqrt{Var (X)\times Var(Z)}} \\=\frac{12}{\sqrt{9\times25}} \\=0.80$

(3)

Compute the value of Corr (Y, Z)-

$Corr (Y, Z) = \frac{Cov (Y, Z)}{\sqrt{Var (Y)\times Var(Z)}} \\=\frac{14}{\sqrt{16\times25}} \\=0.70$

(4)

Compute the value of E (3X+4Y-3Z)-

$E(3X+4Y-3Z)=3E(X)+4E(Y)-3E(Z)\\=(3\times100)+(4\times120)-(3\times130)\\=390$

(5)

Compute the value of Var (3X-3Z)-

$Var (3X-3Z)=[(3)^{2}\times Var(X)]+[(-3)^{2}\times Var (Z)]+(2\times3\times-3\times Cov(X, Z)]\\=(9\times9)+(9\times25)-(18\times12)\\=90$

(6)

Compute the value of Var (3X+4Y-3Z)-

$Var (3X+4Y-3Z)=[(3)^{2}\times Var(X)]+[(4)^{2}\times Var(Y)]+[(-3)^{2}\times Var (Z)]+[(2\times3\times4\times Cov(X, Y)]+[(2\times3\times-3\times Cov(X, Z)]+[(2\times4\times-3\times Cov(Y, Z)]\\=(9\times9)+(16\times16)+(9\times25)+(24\times-10)-(18\times12)-(24\times14)\\=-230$

But this is not possible as variance is a square of terms.

(7)

Compute the value of Cov (3X, 2Y+3Z)-

$Cov(3X, 2Y+3Z)=Cov(3X,2Y)+Cov(3X, 3Z)\\=6Cov(X, Y)+9Cov(X,Z)\\=(6\times-10)+(9\times12)\\=48$

4 0

3 years ago